You can use the fluid's internal lights to preview the lighting effects applied to your fluid simulation. Fluid internal lights include directional, point, diagonal, and ambient lights that display in the Maya workspace when you playback your simulation. You can then use the lighting setup to render the effect. Fluid internal lights have many of the same options as scene lights, including Point Light Decay, Intensity (Brightness), and Color.
Turn off Real Lights to ignore the scene lights and instead use the selected fluid internal light for rendering. Using internal lights makes fluid renders faster, especially if Self Shadowing is on.
To help position internal point and directional lights, you can create a real point light and connect its Translate X, Y, and Z attributes to the fluidShape node’s internal point and direction lights. You can select the point light and use the Move Tool to position the internal lights. For information about connecting attributes, see Connection Editor.